February 27, 2008

New Moon Map Is Best Ever

Earthlings have mapped the moon's surface for the past 4,000 years, but
NASA's latest view is the best yet.

Scientists have created a new map of the south lunar pole with Earth-based
telescopes that is 50 times more detailed than the last version, created with
data from the Clementine spacecraft in 1994.

"This data is the highest resolution and the highest accuracy that's
ever made of lunar south polar region," said Scott Hensley, a scientist at
NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.. Hensley and others
announced the new map from the third Space Exploration Conference in Denver.

In detail of 215 square feet (20 square meters) per pixel, the map shows
craters four times deeper than the Grand Canyon and hundreds of miles wide.

"It has some of the most
incredible topography in the entire solar system," said Eric de Jong,
also at JPL, of the region.

NASA officials said they'll use the new map to scout the rugged terrain for
robot or human landing sites, as well as investigate some longstanding lunar
mysteries.

Crater caches?

Many of the craters imaged have never seen direct sunlight because of their
depth and location.

Such permanently shadowed areas, some scientists think, are prime spots to
search for water ice
or hydrogen deposits that would normally evaporate into space from solar
heating. Other observations have suggested something's there.

Whether or not the deposits spacecraft have detected are water ice or hydrogen,
such lunar caches could become valuable energy, air and water for visiting
astronauts.

"The image[s] ... will help us figure out where we want to go," said
Kelly Snook, a lunar scientist at NASA Ames in Moffett Field, Calif., of future
lunar exploration missions. "They also provide us with unique ability to
answer the fundamental science questions."

Snook called the moon a "unique window" to the early solar system,
explaining that the lunar surface has been witness to billions of years of
planetary evolution.

Radar in space

To create the new map, scientists employed NASA's Goldstone Solar System
Radar facility in the Mojave Desert.

A team of scientists there bounced
microwave beams off the craggy bottom of the moon when it wobbled into view
- a cycle it repeats about every month. The 3-D radar data gathered with two
telescopes on three separate occasions was used to compile the new map.

"We had the best opportunity in 17 years for these observations,"
Hensley said, explaining that the moon's wobble was exaggerated most in 2006
when the team made their observations.

Some of the features mapped are so deep that Earth's largest volcano, Mauna
Loa in Hawaii, would fit neatly inside some of the craters, Hensley said.

"It's quite impressive topography that we have here," he said.

Better maps to come

Doug Cooke at NASA Headquarters in Washington, D.C. said NASA's upcomingLunar Reconnaissance Orbiter (LRO) will soon map the entire moon in even more
detail in the next few years.

"We will be getting better data," Hensley said of LRO, "...but
this [map] is a big step in our understanding of this very interesting
place."

All of the information should be a boon to astronauts who might visit the
rough terrain of south lunar pole in the future, but in either case Hensley
said simply sending spacecraft won't allow us to fully understand our lunar
companion.

"This type of information is critical for us in understanding what
we're getting into," Cooke said. "... [but] to really understand it, it
takes going there and seeing first-hand what you've got."